Automatic small arm

ABSTRACT

This automatic small arm mechanism provides the locking of the firing members by means of an independent member adapted to engage the intermediate lock member controlled automatically by the inertia block or manually. Thus, the main lock bolt will lock the intermediate lock member when the breech block is in its closed position, whereby the striker return spring may be as strong as desired and necessary since the return movement of the independent percussion member has no incidence whatsoever on the lock bolt position.

Elite ttes atent 1 1 1111 3,901,126 Bretton Au 26, 1975 [54] AUTOMATIC SMALL ARM 2,765,557 10/1956 Roper 42 17 2,960,011 11 1960 B tt 89 182 [76] Inventor: Rene Jean Georges Bretton, 26, rue re on A1exander-PourceL Saint-Etienne, Fra Primary ExaminerStephen C. Bentley [22] d A 1 19 4 Attorney, Agent, or FirmWaters, Schwartz & Nissen 1e pr.

[21] Appl. No.: 457,141

[57] ABSTRACT Related US. Application Data [63] Continuation of Scr. No. 236,718, March 21, 1972, This automatic small arm mechamsm Pmwdes the abandoned. locking of the firing members by means of an independent member adapted to engage the intermediate lock [30] Foreign Application priority Data member controlled automatically by the inertia block 25 1971 F N 7111421 or manually. Thus, the main lock bolt will lock the inrdncc termediate lock member when the breech block is in [52] US Cl. n 89/182, 42/17, 89/190 its closed position, whereby the striker return spring [51] Int 2 i I i i i I I i I F411) 3/04 may be as strong as desired and necessary since the [58] Fie'ld z j 183 return movement ofthe independent percussion mem- I ber has no incidence whatsoever on the lock bolt posi- [56] References Cited UNITED STATES PATENTS 5 Claims, 22 Drawing Figures 2,732,768 1/1956 Browning 89/182 2 /a 28 42 r4 17 g PATENTEMuszsma sum 2 [1F 5 PATENTEMueesms 1 126 F/G. l9

3 TT////////// A z PATENTEU M26 1975 AUTOMATIC SMALL ARM CROSS-RELATED APPLICATION This application is a continuation of copending application Ser. No. 236,718, filed Mar. 21, 1972, now abandoned.

FIELD OF THE INVENTION The present invention relates to improvements in or with regard to automatic small arms of the type described and illustrated in US. Pat. No. 2,960,011 of Nov. 15, 1960, Le. small arms wherein the recoiling portion controlling the release of the breech block consists of the complete weapon, except a small inertia block housed in the breech case and adapted to slide freely therein; this inertia block is also adapted to control in proper time the release of said breech block by relative slipping due to its inertia enabling this unit, as the firearm recoils against the shooters shoulder, to remain stationary in space.

DESCRIPTION OF THE PRIOR ART In small arms of this type, the percussion hammer acts jointly as a locking member associated with an intermediate lock or breech bolt.

On the other hand, the automatic supply of ammunition from the magazine takes advantage of the inertia of the cartridges during the recoil period for permitting the free action of a catch consisting of a single, springforming part.

SUMMARY OF THE INVENTION:

While preserving the general features characterizing the above-mentioned automatic small arm, the present invention is directed to provide certain improvements thereto in order to improve the reliability and regularity of its operation.

Firstly, the fact that the percussion hammer has the twofold function of acting as a lock bolt and being an integral part thereof may be a cause of faulty operation, since it is extremely difficult to obtain a proper balance between the force of the locking percussion spring and the force of the hammer return spring; In fact, to avoid accidental percussions likely to occur when the breech block closes the barrel and the pin, driven by its inertia, continues its forward stroke, a relatively strong return spring must be used, otherwise the cartridge will be struck before the barrel is closed, since the lock-bolt forming percussion hammer was not released by the shooter. Conversely, if this spring is too-powerful, it is liable to kick the hammer back during the striking period, before the gas pressure resulting from the load has dropped, thus causing a premature release or trigger ing.

It is the primary object of the present invention to eliminate these risks;

Basically, the invention comprises locking the system by means of a separate member adapted to engage the intennediate lock bolt controlled automatically by the inertia block or by hand. Under these conditions, the lock bolt proper or main bolt will lock the intermediate bolt when the breech block is in its closing position, so that the return spring associated with the striker can be as strong as necessary since the recoil or backward movement of the independent percussion hammer cannot exert any influence whatsoever on the bolt position.

Another object of this invention relates to improvements in the catch-blade. Since this catch-blade consisted heretofore of a single member, the cartridge delivered from the magazine was retained in its locked position as long as the breech block had not been moved home in the backward direction, so that only .a very short time was available for permitting the tilting of this blade and the movement of said cartridge from the magazine to the transfer trough provided for presenting the cartridge in proper alignment with the barrel axis. Therefore, there was a serious risk of misfire on account of a faulty supply.

With the present invention this catch-blade is divided into two elements and is no longer dependent on the position of the breech block. Therefore, the aligning or transfer trough receives the cartridge at the best possible moment since this feed time can take place between beginning of the recoil to the moment when the breech block, after its backward stroke, returns forwards and actuates the rocker.

According to this invention, the two component elements of this catch-blade are both pivoted to a common axis and each is provided with a separate spring having the function of causing one element to project while retracting the other element, respectively, one of these elements comprising a heel adapted to bear against a resilient lamellar portion of the other element, whereby when the magazine is being refilled with fresh cartridges the element provided with said heel can act upon the lamellar portion of the other element and thus bend the same before subsequently returning to the position in which it can perform its catch function.

It is another object of this invention to provide means to enable the small arm in a safety position by keeping the obturator in its mid-stroke of substantially midstroke position, with the possibility or resuming instantaneously the firing position by simply depressing the trough catch button.

This improvement is obtained by providing notches in the sliding surface of the breech block engaged by the rocker, a nose of this rocker being thus adapted to penetrate into one of said notches in order to hold this unit in the safety position until the trough is released by depressing its catch button, so that the rocker can move out from said notch and thus release the breech block for restoring and locking same in its closing position.

It may be pointed out that in this safety position the breech block keeps the percussion hammer in its cocked position so that even if the trigger were depressed the hammer cannot be released, since it is retained under the breech block.

Furthermore, it is advantageous to permit the forward movement of the breech block before the trough is released.

To this end and according to another object characterizing this invention, a'shoulder is provided on the surface of the breech block slidably engaged by said rocker, for limiting the upward movement of the trough while maintaining the latter in an intermediate position.

BRIEF DESCRIPTION OF THE DRAWINGS:

Reference will now be made to the accompanying drawings illustrating diagrammatically by way of example a typical embodiment of this invention. In the drawings:

FIG. 1 is a front view of the intermediate lock bolt;

FIGS. 2 and 3 are a front view and a side view, respectively, of the main lock bolt;

FIG. 4 illustrates the percussion hammer;

FIG. 5 is a front view of the member permitting the manual locking action;

. FIG. 6 is a side-elevational view of the breech block;

FIGS. 7 and 8 are a plan view from beneath and a side-elevational view, respectively, of the manual control member;

FIGS. 9 and 10 illustrate in side-elevational view and in plan view from above, respectively one of the component elements of the catch-blade;

FIGS. 11 and 12 are two similar views of the second component element of this catch-blade;

FIG. 13 is a general, partly elevational, partly sectional view of the complete mounting;

FIG, 14 is a view similar to FIG. 13 but showing the locking system in greater detail FIG. 15 is a similar view showing the breech block during the unlocking movement;

FIGS. 16 and 17 illustrate the mode of operation of the catch-blade;

FIGS. 18 and 19 illustrate the assembly in the cocking position and when the breech block was released and allowed to move forwards;

FIGS. 20 and 21 illustrate the mode of operation of the feed trough, and

FIG. 22 shows the safety position.

DESCRIPTION OF THE PREFERRED EMBODIMENT:

Referring in general to the drawings the reference numerals designate the corresponding elements as follows: 2 the breech case, 3 the breech block, 4 a manual control lever; 5 a push-button for releasing said block, 6 a trigger with its subguard 7, 8 a cartridge magazine and 9 the barrel.

In the breech case 2 a lower aperture 10 if formed. The breech block 3 is slidably mounted in the breech case and comprises essentially: I

the striker or percussion member 11 with its return spring 12,

a sliding plate 13 rigid with the hand control lever 4 and biased by a return spring 14, against a stop member 15 carried by said block 3,

a pivoted extractor 16,

a pair of bores 17 corresponding to rods 18 of the breech case and receiving therein springs 19 for urging the breech or block in the forward direction, transfer trough 20 referred to hereinafter as the a transfer member biased by a spring 21 and formed with a driving shoulder 22 (FIGS. 21 and 22), the transfer member being pivotably mounted on a pivot pin 23 carried by the breech case and movable in said case above its lower aperture 10, a rocker or tumbler 24 also formed with a shoulder 25 coacting with the shoulder 22 of said transfer member 20, and a nose 26, said rocker being pivotably mounted on another pivot pin 27,

a percussion hammer 28 proper, biased by a spring 29 and pivoted about the pivot pin 27, an inertia block 30 formed with a notch 31 engaged by the trigger 6 for guiding the latter and permitting its free longitudinal movement against the force of a spring 32 which, by reacting against notch 31 and said trigger, normally urges the inertia block 30 against the rear bottom of breech case and a blade assembly, hereinafter referred to as the catchblade, comprising two component elements 33, 34, disposed against one of the side walls of the breech case and housed in a recess 35 therein.

The breech or block 3 is locked in position by a lock bolt 36 under the action of a spring 52. Pivoted to this lock bolt 36 is the percussion hammer 28 adapted to engage the striker 11. This lock bolt controls, through its shoulder 37 the breech block 3 through an intermediate lock member 38 by engaging a shoulder 39 provided on member 38. The intermediate lock member 38 comprises has another shoulder 40 adapted to engage the block 3 for locking the same.

The breech block 3 is released automatically, upon firing, by engagement of the inertia block 30 at 41 of the lock bolt 36, so as to pivot the same and release the intermediate lock member 38.

A lug 42 is pivotably mounted on the pin 23 of intermediate lock member 38 and engages the lock bolt 36. To obtain manual release, the lug 42 is carried along by a projection 43 carried by the sliding plate 13 of manual control lever 4.

The element 33 of the catch-blade comprises at its front end a beak 44 and at its rear end a heel 45. The element 33 is pivoted at 46 to the other element 34, the element 34 comprising a resilient blade or portion 47 engageable by the heel 45 of element 33. Each element 33, 34 further comprises a separate return spring 50, 5 l, respectively. Moreover, the catch-blade may be controlled manually by means of the push-button 5 constantly engaging the end 52 of element 34.

The blok 3 comprises on its face slidably engaged by rocker 24 one or a pluraliy of notches 48 and a shoulder 49 whereby, when the block 3 is moved to its safety position (FIG. 22), substantially at mid stroke, the nose 26 of rocker 24 can penetrate into the corresponding notch, thus locking block 3 against movement, the percussion hammer remaining nevertheless in its cocked position but still locked since it is retained under the block.

The aforesaid shoulder 49 permits the forward movement of block 3 when the trough 20 is released.

Of course, this invention, should not be construed as being strictly limited to the specific form of the embodiment shown and described herein, since various modifications and variations may be made thereto without departing from the spirit and scope of the invention as set forth in the appended claims.

What I claim as new is:

1. A firearm having an automatic ammunition feed and comprising a casing with a barrel in prolongation of the case, a displaceable breech block in said case, an inertia block freely slidable in said case, means for locking said breech block in an operative position for firing of the firearm and for releasing the breech block, after firing, for movement to a retracted position for feed of a fresh cartridge to the barrel, said means comprising a lock bolt mounted in said case adjacent the inertia block for movement between a first and a second position, and an intermediate lock member mounted in said case to engage said breech block and in turn be engaged by said lock bolt, when the latter is in said first position, to lock the breech block in said operative position, said inertia block acting on said lock bolt, by the action of recoil forces upon firing, to

cause the lock bolt to move to said second position and release the intermediate lock member to enable the breech block to move to its retracted position; and a spring-loaded percussion hammer pivotably mounted in said case for movement independently of said lock bolt for firing a cartridge.

2. A fireann as claimed in claim 1 comprising means cooperating with said breech block for feeding cartridges from a magazine to said barrel and including a transfer trough for receiving a cartridge from the magazine to feed said cartridge to the barrel, and a catch blade mechanism between said magazine and trough.

3. A firearm as claimed in claim 2 wherein the catch blade mechanism comprises two component elements pivoted about a common axis and each provided with a separate return spring, one of said two component elements including a beak at one end for holding the last cartridge in the magazine in place, and a heel at its opposite end, the other of said two component elements including a resilient lamellar portion engageable with said heel, whereby during the feed of a cartridge to the magazine the element provided with said heel engages the lamellar portion of the other element and deflects same, said element with the beak, during its subsequent return movement, being positioned for acting as a catch member for the first cartridge to be fed from the magazine to the trough.

4. A firearm as claimed in claim 3 comprising a rocker member including a projection facing said breech block to ride thereon, said breech block having anotch for receiving said projection to hold the breech block in a safety position.

5. A firearm as claimed in claim 3 comprising a rocker member acted on by said transfer trough to ride on said breech block, said breech block having a shoulder on the surface of the block on which the rocker rides, said shoulder limiting upward movement of the transfer trough. 

1. A firearm having an automatic ammunition feed and comprising a casing with a barrel in prolongation of the case, a displaceable breech block in said case, an inertia block freely slidable in said case, means for locking said breech block in an operative position for firing of the firearm and for releasing the breech block, after firing, for movement to a retracted position for feed of a fresh cartridge to the barrel, said means comprising a lock bolt mounted in said case adjacent the inertia block for movement between a first and a second position, and an intermediate lock member mounted in said case to engage said breech block and in turn be engaged by said lock bolt, when the latter is in said first position, to lock the breech block in said operative position, said inertia block acting on said lock bolt, by the action of recoil forces upon firing, to cause the lock bolt to move to said second position and release the intermediate lock member to enable the breech block to move to its retracted position; and a spring-loaded percussion hammer pivotably mounted in said case for movement independently of said lock bolt for firing a cartridge.
 2. A firearm as claimed in claim 1 comprising means cooperating with said breech block for feeding cartridges from a magazine to said barrel and including a transfer trough for receiving a cartridge from the magazine to feed said cartridge to the barrel, and a catch blade mechanism between said magazine and trough.
 3. A firearm as claimed in claim 2 wherein the catch blade mechanism comprises two component elements pivoted about a common axis and each provided with a separate return spring, one of said two component elements including a beak at one end for holding the last cartridge in the magazine in place, and a heel at its opposite end, the other of said two component elements including a resilient lamellar portion engageable with said heel, whereby during the feed of a cartridge to the magazine the element provided with said heel engages the lamellar portion of the other element and deflects same, said element with the beak, during its subsequent return movement, being positioned for acting as a catch member for the first cartridge to be fed from the magazine to the trough.
 4. A firearm as claimed in claim 3 comprising a rocker member including a projection facing said breech block to ride thereon, said breech block having a notch for receiving said projection to hold the breech block in a safety position.
 5. A firearm as claimed in claim 3 comprising a rocker member acted on by said transfer trough to ride on said breech block, said breech block having a shoulder on the surface of the block on which the rocker rides, said shoulder limiting upward movement of the transfer trough. 